Part 4

SERVICE COLUMN LOCK INDICATOR

The service column lock indicator gives an indication to the vehicle operator when the RF hub has recorded a DTC for a steering column shaft lock module circuit or component malfunction. This indicator is controlled by the IC logic circuit based upon programming and electronic messages received by the IC from the RF hub over the CAN data bus.

The service column lock indicator function of the electronic display unit is completely controlled by the IC logic circuit, and that logic will only allow this indicator to operate when the IC receives a battery current input on the fused ignition output (run-start) circuit. Therefore, the service column lock indication will always be OFF when the ignition switch status is anything except ON or START. The IC will turn ON the service column lock indicator for the following reasons:

- Service Column Lock Indicator Lamp-On Message - Each time the IC receives an electronic service column lock indicator lamp-ON message from the RF hub, the service column lock indicator will be illuminated. The indicator remains illuminated for about five seconds, until the IC receives a lamp-OFF message from the RF hub, until the IC arbitrator logic determines that another display request has priority, or until the ignition switch status transitions to OFF, whichever occurs first.

The RF hub continually monitors the steering column shaft lock module circuits and components to determine the condition of the system. The RF hub then sends the proper lamp-ON or lamp-OFF message to the IC.

For proper diagnosis of the shaft lock module, the RF hub, the IC, the CAN data bus or the electronic communication related to service column lock indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.

TRACTION CONTROL INDICATOR

The traction control indicator gives an indication to the vehicle operator when the Electronic Stability Control (ESC) / Traction Control System (TCS) has been activated. This indicator is controlled by the IC logic circuit based upon programming and electronic messages received by the IC from the CAB over the CAN data bus. The IC will illuminate the traction control indicator for about four seconds as a bulb test each time the ignition switch status transitions to ON.

The traction control indicator is completely controlled by the IC logic circuit, and that logic will only allow this indicator to operate when the IC receives a battery current input on the fused ignition output (run-start) circuit. Therefore, the indicator will always be OFF when the ignition switch status is anything except ON or START. The indicator only illuminates when it is provided a path to ground by the IC circuitry. The IC will turn ON the traction control indicator for the following reasons:

- Traction Control Indicator Lamp-On Message - Each time the IC receives an electronic traction control indicator lamp-ON message from the CAB indicating that the ESC/TCS has been activated, the traction control indicator will be illuminated. The indicator can be flashed ON and OFF, or illuminated solid, as dictated by the CAB message. The indicator remains illuminated solid or continues to flash until the IC receives a lamp-OFF message from the CAB, or until the ignition switch status transitions to OFF, whichever occurs first.

The CAB continually monitors the traction control switch to determine the proper outputs to the components of the Antilock Brake System (ABS). The CAB then sends the proper lamp-ON or lamp-OFF message to the IC.

For proper diagnosis of the traction control switch, the ESC/TCS, the CAB, the IC, the CAN data bus or the electronic communication related to traction control indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.

TRANSMISSION TEMPERATURE INDICATOR

The transmission over-temperature indicator gives an indication to the vehicle operator when the transmission fluid temperature is excessive, which may lead to accelerated transmission component wear or failure. This indicator is controlled by the IC logic circuit based upon programming and electronic messages received over the CAN data bus from the TCM.

The transmission over-temperature indicator function of the electronic display unit is completely controlled by the IC logic circuit, and that logic will only allow this indicator to operate when the IC receives a battery current input on the fused ignition output (run-start) circuit. Therefore, the transmission over-temperature indication will always be OFF when the ignition switch status is anything except ON or START. The IC will turn ON the transmission over-temperature indicator for the following reasons:

- Trans Over-Temp Indicator Lamp-On Message - Each time the IC receives an electronic trans over-temp indicator lamp-ON message from the TCM indicating that the fluid temperature is too high, the transmission over-temperature indicator will be illuminated and a single chime tone is sounded. The indicator remains illuminated for about five seconds, until the IC receives a lamp-OFF message from the TCM, until the IC arbitrator logic determines that another display request has priority, or until the ignition switch status transitions to OFF, whichever occurs first. The chime tone feature will only repeat during the same ignition cycle if the indicator is cycled OFF and then ON again by the appropriate lamp-ON and lamp-OFF messages from the TCM.

The TCM continually monitors the transmission temperature sensor to determine the transmission operating condition. The TCM then sends the proper lamp-ON or lamp-OFF message to the IC. If the IC illuminates the transmission over-temperature indicator due to a high transmission oil temperature condition, it may indicate that the transmission or the transmission cooling system are being overloaded or that they require service.

For proper diagnosis of the transmission temperature sensor, the TCM, the IC, the CAN data bus or the electronic communication related to transmission over-temperature indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.

TURN SIGNAL INDICATORS

The turn signal indicators give an indication to the vehicle operator that the turn signal (left or right indicator flashing) or hazard warning (both left and right indicators flashing) have been selected and are operating. These indicators are controlled by transistors on the IC cluster electronic circuit board based upon cluster programming and electronic messages received from the BCM over the CAN data bus.

Each turn signal indicator Light Emitting Diode (LED) unit is completely controlled by the IC logic circuit, and that logic will allow this indicator to operate whenever the IC receives a battery current input on the fused B(+) circuit. Therefore, each LED can be illuminated regardless of the ignition switch status. The LED only illuminates when it is provided a path to ground by the IC transistor. The IC will turn ON the turn signal indicators for the following reasons:

- Turn Signal Indicator Lamp-On Message - Each time the IC receives an electronic right or left turn signal indicator lamp-On message from the BCM over the CAN data bus, the appropriate turn signal indicator will be flashed on and off. The BCM messages to the IC also control the flash rate of the turn signal indicators, as well as the click rate of an electromechanical relay soldered onto the IC electronic circuit board that emulates the sound emitted by a conventional turn signal flasher. The turn signal indicators continue to flash on and off until the IC receives a lamp-OFF message from the BCM, or until the ignition switch status transitions to OFF, whichever occurs first.
- Hazard Warning Indicator Lamp-On Message - Each time the IC receives an electronic hazard warning indicator lamp-On message from the BCM over the CAN data bus, both turn signal indicators will be flashed on and off. The BCM messages to the IC also control the flash rate of the turn signal indicators, as well as the click rate of an electromechanical relay soldered onto the IC electronic circuit board that emulates the sound emitted by a conventional hazard warning flasher. The turn signal indicators continue to flash on and off until the IC receives a lamp-OFF message from the BCM.
- Turn Signal-On Textual Warning Message - When the BCM detects that a turn signal has been active continuously for 1.6 kilometers (1 mile) with the vehicle speed greater than 22 kilometers-per-hour (15 miles-per hour) a TURN SIGNAL ON textual message and flashing right or left turn signal icon will appear within the IC electronic display unit and a chime tone will be sounded.
- Lamp Out Mode - If the BCM detects an ineffective turn signal lamp or circuit, it increases the flash rate for the remaining operative turn signals and sends an electronic message to the IC. The IC then increases the flash rate of the turn signal indicators and the click rate of the electromechanical relay to provide an indication of the problem to the vehicle operator.

The IC continually monitors electronic messages from the BCM to determine the proper turn signal and hazard warning indicator operation.

For proper diagnosis of the turn signal and hazard warning system, the multi-function switch, the BCM, the IC, the CAN data bus or the electronic communication related to turn signal indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.

WAIT-TO-START INDICATOR

The wait-to-start indicator gives an indication to the vehicle operator when the diesel engine is too cool for efficient and reliable engine starting, and the engine glow plugs are energized in their preheat operating mode. This indicator is controlled by the IC logic circuit board based upon programming and electronic messages received by the IC from the PCM over the CAN data bus.

The wait-to-start indicator function of the electronic display unit is completely controlled by the IC logic circuit, and that logic will only allow this indicator to operate when the IC receives a battery current input on the fused ignition output (run-start) circuit. Therefore, the indicator will always be OFF when the ignition switch status is anything except ON or START. The IC will turn ON the wait-to-start indicator for the following reasons:

- Wait-To-Start Indicator Lamp-On Message - Each time the IC receives an electronic wait-to-start indicator lamp-ON message from the PCM indicating that the air temperature is too cool for efficient and reliable engine starting and the glow plugs are energized in their preheat mode, the wait-to-start indicator will be illuminated. The indicator remains illuminated until the IC receives a lamp-OFF message from the PCM, until the PCM detects that the engine is running, or until the ignition switch status transitions to OFF, whichever occurs first.

The PCM continually monitors the glow plug control circuits to determine when they are energized in their preheat operating mode. The PCM then sends the proper lamp-ON or lamp-OFF message to the IC. For proper diagnosis of the wait-to-start indicator, the PCM, the IC, the CAN data bus or the electronic communication related to wait-to-start indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.

WASHER FLUID INDICATOR

The washer fluid indicator gives an indication to the vehicle operator that the fluid level in the washer reservoir is low. This indicator is controlled by the IC logic circuit based upon programming and electronic messages received from the BCM over the CAN data bus.

The washer fluid indicator function of the electronic display unit is completely controlled by the IC logic circuit, and that logic will only allow this indicator to operate when the IC receives a battery current input on the fused ignition output (run-start) circuit. Therefore, the washer fluid indication will always be OFF when the ignition switch status is anything except ON or START. The IC will turn ON the washer fluid indicator for the following reasons:

- Washer Fluid Indicator Lamp-On Message - Each time the IC receives an electronic washer fluid indicator lamp-ON message from the BCM indicating that a low washer fluid condition has been detected for 60 consecutive seconds, the washer fluid indicator is illuminated and a single chime tone is sounded. The indicator remains illuminated until the IC receives lamp-OFF messages for 60 consecutive seconds from the BCM, or until the ignition switch status transitions to OFF, whichever occurs first. The chime tone feature will only repeat during the same ignition cycle if the washer fluid indicator is cycled OFF and then ON again by the appropriate lamp-ON and lamp-OFF messages from the BCM.

The BCM continually monitors the washer fluid level switch in the washer reservoir to determine the level of the washer fluid. The BCM then sends the proper lamp-ON or lamp-OFF message to the IC.

For proper diagnosis of the washer fluid level switch, the BCM, the IC, the CAN data bus or the electronic communication related to washer fluid indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.

WATER-IN-FUEL INDICATOR

The water-in-fuel indicator gives an indication to the vehicle operator when there is excessive water in the fuel system. This indicator is controlled by the IC based upon programming and electronic messages received from the PCM over the Controller Area Network (CAN) data bus.

The water-in-fuel indicator is completely controlled by the IC logic circuit, and that logic will only allow this indicator to operate when the IC receives a battery current input on the fused ignition output (run-start) circuit. Therefore, the indicator will always be OFF when the ignition switch status is anything except ON or START. The icon only illuminates when it is provided a path to ground by the IC transistor. Each time the ignition switch status transitions to ON the water-in-fuel indicator is illuminated for about two seconds as a bulb test. The water-in-fuel indicator will be turned ON for the following reasons:

- Water-In-Fuel Indicator Lamp-On Message - Each time the IC receives an electronic water-in-fuel lamp-ON message from the PCM indicating that there is excessive water in the diesel fuel system, the water-in-fuel indicator will be illuminated. The indicator remains illuminated until the IC receives a lamp-OFF message from the PCM, or until the ignition switch status transitions to OFF, whichever occurs first.

The PCM continually monitors the water-in-fuel sensor to determine whether there is excessive water in the diesel fuel system. The PCM then sends the proper lamp-ON or lamp-OFF message to the IC. For proper diagnosis of the water-in-fuel operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.